POI : Java Glossary

An Apache/Jakarta open source project to allow Java to export/import various file
formats including Excel (*.xls) and MS Word (*.doc) If all you need to do is read/write CSV (Comma-Separated Value)
files, you can use the much simpler CSVReader/CSVWriter classes instead.

Other possibilities include creating RDF (Resource Development Framework)
or HTML (Hypertext Markup Language) files. You can also create
any file that OpenOffice can import then
export to Word.

You format Word documents by defining nested styles with
HWPF
then applying styles to hunks of text.

POI is not what I would call developer friendly. You can get the source with
CVS and
build it yourself.
There are some unlabeled binaries you can find by diligently poking around
directories on one of the download mirrors.